Change-speed gearing.



E. FUCHS.

CHANGE SPEED GEARING. APPLICATION FILED DEC-8,1914.

1,1,. Patented. June 15, 1915,

WWW-mg ERNEST FUGHS,OF IBILLANCOURT, FRANCE, ASSIGNOR TO LOUIS RENAULT, F

BILLANGOUBT," FRANCE. I

CHANGE-SPEED GEARING.

antacids 0 Application filed December 8, 1914. Serial N 0. 876,055.

TO-aZZ whom it may concern: Be it known that I, Emsnsr Focus, citizen of the French Republic, residing at Billancourt, Department of the Seine, in France, have invented certain new and useful Improvements in or Relating to Change- Speed Gearing; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the artlto which it appertains to make and use the same.

The invention relates to a change speed gearing having helically toothed gear wheels mainly used in automobile vehicles in order to obtain a silent transmission; In this gearing the sliding pinions formed with helical teeth slide upon a shaft formed with helical grooves or keys directedin the same direction and having substantially the same pitch as the teeth of'the pinions. The lateral reaction produced by the inclination of the teeth is thus compensated by the reaction produced by the inclination .of the grooves or driving keys provided on the shaft. In this manner, all efforts upon the forks of the sliding pinions for maintaining the pinions in engagement, are avoided.

The annexed drawing shows in section and by way of an example a change speed gearing in accordance with the invention. The gearing is of the ordinary four speed 1 type, and comprises a driving shaft 1, a driven shaft 2 mounted in alinement with the driving shaft, and a secondary shaft 3.

Upon the end of shaft 1 within the change speed gearing, a pinion 4: is mounted, having helical teeth inclined in the suitable direction, for instance. in the illustrated case, toward the right. .This pinion is always in engagement with a helical wheel 5 carried by the secondary shaft 3. A sliding pinion 6 having helical teeth may be either caused to engage with a wheel 7 integral with the shaft 3, or/be coupled through the medium of special teeth, with the pinion 4: in order to obtain a direct drive. The sliding pinion pinion 6. In this manner its lateral reaction compensates that received by the pinion 6 as will be more fully described hereinafter. The pinion 6 is formed upon its face turned 7 This change speed gearing operates in the toward the pinion 4, with internal teeth 9 adapted toengage the pinion 4 or more exactly, with the .special teeth 10 of the pin- 1on4. In order to obtain the other two speeds, use may be made of sliding'double change speed pinions 11, 12, sliding upon the shaft 2 and adapted to be caused to engage eitherwith a pinion 13 or with a pinignftlca both integral with the secondary s a following manner: For the third speed, the sl dlng pinion is brought into engagement wlth the gear wheel 7. It will be noted that the pinions 4, l0 and 7 are so-called driving pinions, while the gear wheels 5, and 6 are so-called driven pinions. Th'e pinion 4c is driyen from the'shaft l'in the direction indicated by the arrow or and as its helix is a r ght handed one and it is a driving plnion, it receives a lateral thrust directed in the direction indicated by the arrow 6, this reaction is supported by an end I thrust ball bearing. The helical pinion 5 rotates in the direction indicated by the arrow 0," it is a driven pinion and receives a thrust in the direction indicated by the arrow 03. With regard to the pinion 7 which is a driving pinion, it rotates in the direction indicated by the arrow 6 and receives a lateral thrust in the direction indicated by the arrow 7 which compensates the lateral thrust of the pinion 5. The sliding pinion 6 is a driven pinion and rotates in the direction indicated by the arrow 9; it receives a reaction directed in thedirection indicated by the arrow h. The pitch of the helix formed on the shaft 2 is substantially equal to that of the teeth of the pinion 6 and the inclination of the grooves being in 95 the same direction as that of the teeth of the same/ pinion, the reaction produced by the grooves is directed according to the arrow i and compensates the reaction it received by the pinion'6 then in engagement me with the pinion.

In order to obtain a direct drive, the pinion 10 integral with the pinionA is brought into engagement with the teeth 9 of the pinions 6. The reaction of the pinion 4 is di- 105 rected in the direction indicated by the arrow I) while the reaction received by the pinion 6 the teeth 9 of which are in engagement with the pinion 10, is directed in the direction indicated by the arrow h oppono the arrow it produced by place in the case of the pinion 6 when it is sate one another.

in engagement with the pinion 7, the effort coming either from the engine or from the transmission driving the engine through the medium of the helical teeth formed on the shaft 2. All the reactions are equilibrated and the forks controlling the sliding pinions are not subjected to any effect for maintaining the pinions in engagement.

The pinions 11, 12, 13, 14 are pinions with straight teeth in the case of the construction illustrated; it is evident that they may be also formed with helical teeth mounted in such a manner that the reactions compen- In the latter case, the inclination of the teeth will be selected so as to be consistent with the dimensions of the pinions in use. inclination should be the same as that of the teeth of the pinion 6. It will be merely necessary to give the helical grooves or keys formed upon the shaft 2 on which the pinions 11 and 12 slide, inclinations in the same There is no reason Why this direction and of substantially the same pitches as those of the teeth formed on these pinions. The pinions at and 5 illustrated with helical teeth may be also formed with straight teeth. The advantage of the ar rangement adopted consists in the compensation of the lateral thrusts borne by the shaft 3 and produced by the teeth of the pinions '7 and 5.

I claim:

1. Transmission gearing comprising two rotary shafts, meshing gears carried by said shafts having helical teeth,'and a helical sliding connection between one of said gears and its shaft, for the purpose described.

2. Transmission gearing comprising two rotary shafts, meshing gears carri d by said shafts having helical teeth, a sliding connection between at least one of the gears andits shaft capable of compensating for the end thrusts of the sliding gear caused by said helical teeth. r

3. Change speed gearing comprising a driving shaft, an intermediate shaft and a driven shaft,.a sliding gear on one of said shafts, a gear mounted on an adjacent shaft, said gears having me hing helical teeth and said sliding gear having a helical sliding .connection with its shaft, for the purpose described.

In testimony whereof I affix my signature, in presence of two witnesses.

, V ERNEST FUCHS. Witnesses: 7

DAVID'G. PooLE, J12, HENRI COHEN. 

